Hi, I'd be really grateful for some help. I've created a sidebar but it won't align with my posts, it just sits above them leaving a big bit of empty space between my navigation bar and my posts. How can I fix it so the sidebar sits next to the posts without leaving the gap?

At the moment it looks like this http://avgc.tumblr.com

Thanks a lot in advance!

this is my html code:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">

<head>

<p><a href="http://avgc.tumblr.com" title="avgc"><center><img style="width: YYpx; height: YYpx; border: 0;" src="http://static.tumblr.com/863tqum/GR7m6n8fb/header.jpg" width="700" length="2600" alt="Text Description"></center></a></p>
<link rel="shortcut icon" href="{Favicon}" />
{block:Description}<meta name="description" content="{MetaDescription}" />{/block:Description}
<title>{Title}{block:SearchPage}: {lang:Search results for SearchQuery}{/block:SearchPage}{block:PostSummary}: {PostSummary}{/block:PostSummary}</title>
<title><?php
if (is_home()) {
bloginfo('name');
} elseif (is_404()) {
echo '404 Not Found'; echo ' | '; bloginfo('name');
} elseif (is_category()) {
echo 'Category:'; wp_title(); echo ' | '; bloginfo('name');
} elseif (is_search()) {
echo 'Search Results'; echo ' | '; bloginfo('name');
} elseif ( is_day() || is_month() || is_year() ) {
echo 'Archives:'; wp_title(); echo ' | '; bloginfo('name');
} else {
echo wp_title(); echo ' | '; bloginfo('name');
}
?></title>
<!-- Default values -->
<meta name="text:Header slogan" content="is a tumblelog." />
<meta name="color:Background" content="#FFFFFF"/>
<meta name="color:Link" content="#346B9A"/>
<meta name="color:Link hover" content="#9A6934"/>
<meta name="font:Body" content="Georgia, serif"/>
<meta name="font:Date" content="Helvetica, Arial, sans-serif"/>
<meta name="if:Show notes" content="0">
<meta name="if:Show album art on audio posts" content="1" />
<meta name="text:Disqus Shortname" content="" />
<meta name="if:Show comment count on frontpage" content="0" />
<style>
/* General styling */
body {

background: {color:Background};
font: 14px/20px {font:Body};
}


h1 { width: 540px; margin: 0 auto; }
h1 a, h1 {
color: #000; line-height: 1.2;
text-decoration: none;
font-family: Georgia, serif;
font-size: 19px;
font-weight: normal;
}

h1 a:hover { color: inherit; }
h2 { margin-top: 0; font-size: 16px; }
/* "fake smallcaps" */
h3 { font-size: 12px; text-transform: uppercase; letter-spacing: 2px; }
object { margin-bottom: 1em; margin-top: 0.5em; }
sup { line-height: 1; }
p, pre { margin-top: 0; padding-top: 0; }
img { display: block; margin-bottom: 20px; margin-top: 5px; }
a { color: {color:Link}; text-decoration: none; }
a:hover { color: {color:Link hover}; }
a img { outline: 0; border: none; }
blockquote {
width: 470px;
margin-left: -30px;
padding-left: 30px;
color: #222;
/* This is the quote mark in the left corner (also, the only image
in this theme). Remove if you don't want it. */
background: url(http://static.tumblr.com/sajzoro/2pUkqr1t1/aster.png)
top left no-repeat;
font-style: italic;
margin-top: 0;

}
/* Make nested blockquotes behave. */
blockquote blockquote { margin-left: 0; }
/* ems in blockquotes look like normal text. Could be confusing; should work
fine unless there is a giant em block at the end of the blockquote, or
worse, making up the whole blockquote. Remove if you don't want to take
that risk, but instead suffer from a lack of distinguished emphasis in
blockquotes. */
blockquote em { font-style: normal; }
blockquote ul, blockquote ol { padding-left: 2em; }
ul, ol { padding-left: 0; }

/* Specific elements. */
div#head {
padding: 60px;
}
div#main {
width: 800px;
margin: 0 auto;



}
a#past { float: left; }
a#future { float: right; margin-right: 4px; }
span#page { float: left; width: 300px; text-align: center; color: #666; }
div#last { margin-bottom: 2em; }
ul#bottom {
list-style: none; padding-top: 0; margin-top: 0; padding-left: 0; margin-left: 0;
width: 340px; float: left; margin-bottom: 2em;
}
ul#bottom li {
float: left; margin-right: 40px; padding-left: 0;
}
div#foot {
width: 540px; margin: 0 auto;
margin-bottom: 40px;
}



/* Various repeated elements. */
span.permalink {
float: left; width: 130px;
font-size: 12px;
font-family: {font:Date};
}
span.permalink a {
font-weight: bold;
text-decoration: none;
}

div.realpost {
float: left;
width: 650px;
margin-bottom: 4em; padding-top: 0; margin-top: 0;
}



{block:IfShowNotes}div.realpost { margin-bottom: 6em; }{/block:IfShowNotes}
{block:IfShowCommentCountOnFrontpage}
div.realpost { margin-bottom: 6em; }
{block:IfShowNotes}div.realpost { margin-bottom: 7em; }{/block:IfShowNotes}
{/block:IfShowCommentCountOnFrontpage}

body#permalink-page div.realpost {
margin-bottom: 2em;
}

div.realpost div {
/* sorry, css gods */
width: 500px;
padding-top: 0;
}
div.audio embed { margin-top: .3em; margin-bottom: 1em; }
img.album-art { float: right; padding-left: 2em; height: 100px; width: 100px; }

div.chat ol {
list-style: none; margin-top: 0;
}
span.label { font-weight: bold; }
h2 { margin-top: 0; font-size: 16px; }
div.text h2 a { color: #000; }
/* In case you want to quote in quote post, we need to distinguish
*the* quote from any other blockquotes in the post. (No yo dawgs
here. It might be useful.) */
blockquote.thequote {
font-size: 1.25em; line-height: 1.3; color: #000;
}

div.text img {
max-width: 500px
}
div.text blockquote img {
max-width: 150px
}

ol.notes {
font-size: 12px;
font-family: {font:Date};
list-style-type: none;
margin: 0 0 70px 130px;
}
ol.notes img {
display: none;
}
div.post div.question {
font-weight: bold;
margin-bottom: 1em;
}


{block:IfDisqusShortname}
/* Styling for Disqus comments */
div#disqus_thread {
width: 480px; margin: 0 auto;
padding-right: 60px;
margin-bottom: 2em;
margin-top: -1em;
}

div#disqus_thread h3 {
margin-bottom: 1.5em;
}

div#disqus_thread div#dsq-comments-title { margin-top: 3em; }

body#with-disqus div#it.post {
margin-top: 0;
}

body#with-disqus h1 {
margin-bottom: -2em;
}

body#with-disqus div.realpost {
margin-bottom: 0; padding-bottom: 0;
}

.dsq-comment-header-meta {
font-family: Arial, Helvetica, sans-serif;
}

p#powered-by-disqus {
font-family: Arial, Helvetica, sans-serif;
font-size: 10px;
margin-top: 2em;
text-transform: uppercase;
}

div#disqus_thread .dsq-options {
display: none;
}
{/block:IfDisqusShortname}

.search_query { font-weight: bold; }

{CustomCSS}


</style>
</head>
<body id="{block:IfDisqusShortname}{block:PermalinkPage}with-disqus{/block:PermalinkPage}{/block:IfDisqusShortname}
{block:PermalinkPage} permalink-page{/block:PermalinkPage}">

<div id="head">
<h1><a href="http://avgc.tumblr.com"></a> <em>{text:Header slogan}</em></h1>

<div style="width: 540px; margin: 10px auto 0 auto; display: none; {block:HasPages}display: block;{/block:HasPages}{block:AskEnabled}display: block;{/block:AskEnabled}{block:SubmissionsEnabled}display: block;{/block:SubmissionsEnabled}">
{block:HasPages}
{block:Pages}<a href="{URL}">{Label}</a>&nbsp;&nbsp;&nbsp;{/block:Pages}
{/block:HasPages}
{block:AskEnabled}<a href="/ask">{AskLabel}</a>&nbsp;&nbsp;&nbsp;{/block:AskEnabled}
{block:SubmissionsEnabled}<a href="/submit">{SubmitLabel}</a>{/block:SubmissionsEnabled}
</div>
</div>
<div id="sidebar">

<style><position:fixed;>
# { vertical-align:right;}
# { vertical-align:right;}
</style>
<table>
<tr>
<td id="sidebar"></td>

<td id="contentare"><a title="Follow AVGC on Bloglovin" href="http://www.bloglovin.com/en/blog/3896703"><img alt="Follow on Bloglovin" src="http://www.bloglovin.com/widget/bilder/en/widget.gif" border="0"></a>

<a href="https://twitter.com/aimeevgc" class="twitter-follow-button" data-show-count="false">Follow @aimeevgc</a>
<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>

<a href="http://heartifb.com"><img src="http://heartifb.wpengine.netdna-cdn.com/wp-content/uploads/2012/07/IFB_SEAL_BLACK.gif" alt="IFB"/><img align="right" /></a></td>


</tr>
</table>

</div>

<div id="main">
{block:SearchPage}
<div class="post search">
<span class="permalink">{lang:Search}</span>
<div class="realpost"><div>
{block:SearchResults}
{lang:SearchResultCount results for SearchQuery 2}.
{/block:SearchResults}
{block:NoSearchResults}
{lang:No search results for SearchQuery 2}.
{/block:NoSearchResults}
</div></div></div>
{/block:SearchPage}



{block:Posts}
{block:Link}
<div class="post link">
{block:Date}
<span class="permalink">
<a href="{Permalink}">{ShortMonth} {DayOfMonth}, {Year}</a><br />
{block:IfDisqusShortName}{block:IfShowCommentCountOnFrontpage}<a href="{Permalink}#disqus_thread"></a><br />
{/block:IfShowCommentCountOnFrontpage}{/block:IfDisqusShortName}{block:IfShowNotes}{NoteCountWithLabel}{/block:IfShowNotes}
</span>
{/block:Date}
<div class="realpost"><div>
<h2><a href="{URL}">{Name}</a></h2>
{block:Description}{Description}{/block:Description}
</div></div>
</div>
{/block:Link}
{block:Answer}
<div class="post answer">
{block:Date}
<span class="permalink">
<a href="{Permalink}">{ShortMonth} {DayOfMonth}, {Year}</a><br />
{block:IfDisqusShortName}{block:IfShowCommentCountOnFrontpage}<a href="{Permalink}#disqus_thread"></a><br />
{/block:IfShowCommentCountOnFrontpage}{/block:IfDisqusShortName}{block:IfShowNotes}{NoteCountWithLabel}{/block:IfShowNotes}
</span>
{/block:Date}
<div class="realpost"><div>
<div class="question">{lang:Asker asked}: {Question}</div>
{Answer}
</div>
</div>
{/block:Answer}
{block:Chat}
<div class="post chat">
{block:Date}
<span class="permalink">
<a href="{Permalink}">{ShortMonth} {DayOfMonth}, {Year}</a><br />
{block:IfDisqusShortName}{block:IfShowCommentCountOnFrontpage}<a href="{Permalink}#disqus_thread"></a><br />
{/block:IfShowCommentCountOnFrontpage}{/block:IfDisqusShortName}{block:IfShowNotes}{NoteCountWithLabel}{/block:IfShowNotes}
</span>
{/block:Date}
<div class="realpost"><div>
{block:Title}<h2><a href="{Permalink}">{Title}</a></h2>{/block:Title}
<ol>
{block:Lines}
<li>{block:Label}<span class="label">{Label}</span>{/block:Label}
{Line}</li>
{/block:Lines}
</ol>
</div></div>
</div>
{/block:Chat}
{block:Video}
<div class="post video">
{block:Date}
<span class="permalink">
<a href="{Permalink}">{ShortMonth} {DayOfMonth}, {Year}</a><br />
{block:IfDisqusShortName}{block:IfShowCommentCountOnFrontpage}<a href="{Permalink}#disqus_thread"></a><br />
{/block:IfShowCommentCountOnFrontpage}{/block:IfDisqusShortName}{block:IfShowNotes}{NoteCountWithLabel}{/block:IfShowNotes}
</span>
{/block:Date}
<div class="realpost"><div>
{Video-500}
{block:Caption}{Caption}{/block:Caption}
</div></div>
</div>
{/block:Video}
{block:Audio}
<div class="post audio">
{block:Date}
<span class="permalink">
<a href="{Permalink}">{ShortMonth} {DayOfMonth}, {Year}</a><br />
{block:IfDisqusShortName}{block:IfShowCommentCountOnFrontpage}<a href="{Permalink}#disqus_thread"></a><br />
{/block:IfShowCommentCountOnFrontpage}{/block:IfDisqusShortName}{block:IfShowNotes}{NoteCountWithLabel}{/block:IfShowNotes}
</span>
{/block:Date}
<div class="realpost"><div>
{block:IfShowAlbumArtOnAudioPosts}
{block:AlbumArt}
<img src="{AlbumArtURL}" alt="{block:Artist}{Artist}{/block:Artist}{block:TrackName} - {TrackName}{/block:TrackName}" class="album-art" />
{/block:AlbumArt}{/block:IfShowAlbumArtOnAudioPosts}
{AudioPlayerBlack}
{block:Caption}{Caption}{/block:Caption}
</div></div>
</div>
{/block:Audio}
{block:Photo}
<div class="post photo">
{block:Date}
<span class="permalink">
<a href="{Permalink}">{ShortMonth} {DayOfMonth}, {Year}</a><br />
{block:IfDisqusShortName}{block:IfShowCommentCountOnFrontpage}<a href="{Permalink}#disqus_thread"></a><br />
{/block:IfShowCommentCountOnFrontpage}{/block:IfDisqusShortName}{block:IfShowNotes}{NoteCountWithLabel}{/block:IfShowNotes}
</span>
{/block:Date}
<div class="realpost"><div>
{LinkOpenTag}
<img src="{PhotoUrl-500}" alt="{PhotoAlt}"/>
{LinkCloseTag}
{block:Caption}{Caption}{/block:Caption}
</div></div>
</div>{/block:Photo}
{block:Quote}
<div class="post quote">
{block:Date}
<span class="permalink">
<a href="{Permalink}">{ShortMonth} {DayOfMonth}, {Year}</a><br />
{block:IfDisqusShortName}{block:IfShowCommentCountOnFrontpage}<a href="{Permalink}#disqus_thread"></a><br />
{/block:IfShowCommentCountOnFrontpage}{/block:IfDisqusShortName}{block:IfShowNotes}{NoteCountWithLabel}{/block:IfShowNotes}
</span>
{/block:Date}
<div class="realpost"><div>
<blockquote class="thequote">{Quote}</blockquote>
{block:Source}{Source}{/block:Source}
</div></div>
</div>{/block:Quote}
{block:Text}
<div class="post text">
<span class="permalink">
{block:Date}
<a href="{Permalink}">{ShortMonth} {DayOfMonth}, {Year}</a><br />
{block:IfDisqusShortName}{block:IfShowCommentCountOnFrontpage}<a href="{Permalink}#disqus_thread"></a><br />
{/block:IfShowCommentCountOnFrontpage}{/block:IfDisqusShortName}{block:IfShowNotes}{NoteCountWithLabel}{/block:IfShowNotes}
{/block:Date}
<br />
</span>
<div class="realpost"><div>
{block:Title}<h2><a href="{Permalink}">{Title}</a></h2>{/block:Title}
{Body}
</div></div>
</div>{/block:Text}
{/block:Posts}

{block:IfDisqusShortname}
{block:Permalink}
<div id="disqus_thread">
<script type="text/javascript" src="http://disqus.com/forums/{text:Disqus Shortname}/embed.js"></script>
<noscript><a href="http://{text:Disqus Shortname}.disqus.com/?url=ref">{lang:View the discussion thread}</a></noscript>
<p id="powered-by-disqus">{lang:Blog comments powered by Disqus 2}</p>
</div>
{/block:Permalink}
{/block:IfDisqusShortname}

{block:IfShowNotes}
{PostNotes}
{/block:IfShowNotes}

{block:IndexPage}
{block:Pagination}
<div class="post">
<span class="permalink"><strong>{lang:Navigate}</strong></span>
<div class="realpost"><div>
{block:NextPage}<a href="{NextPage}" id="past">&laquo; {lang:To the past}</a>{/block:NextPage}
<span id="page">{lang:Page CurrentPage of TotalPages}</span>
{block:PreviousPage}<a href="{PreviousPage}" id="future">{lang:To the future} &raquo;</a>{/block:PreviousPage}
</div></div>
</div>
{/block:Pagination}
{/block:IndexPage}

<div class="post last" id="it">
<span class="permalink"><strong>{lang:About}</strong></span>
<div class="realpost" id="last"><div>
{Description}
<a href="{RSS}">{lang:Subscribe via RSS}</a>.
</div></div>
</div>


<div id="foot">
<ul id="bottom">
<li><a href="http://tumblr.com/">Tumblr</a></li>
<li>Theme by <a href="http://dailymeh.tumblr.com/">Simen</a></li>
</ul>
<form action="/search" method="get">
<input type="text" name="q" value="{lang:Search}" onclick="java script:if (this.value == '{lang:Search}') this.value = '';"/>
</form>
</div>

</div>

{block:IfDisqusShortname}
<script type="text/javascript">
//<![CDATA[
(function() {
var links = document.getElementsByTagName('a');
var query = '?';
for(var i = 0; i < links.length; i++) {
if(links[i].href.indexOf('#disqus_thread') >= 0) {
query += 'url' + i + '=' + encodeURIComponent(links[i].href) + '&';
}
}
document.write('<script charset="utf-8" type="text/javascript" src="http://disqus.com/forums/{text:Disqus Shortname}/get_num_replies.js' + query + '"></' + 'script>');
})();
//]]>
</script>
{/block:IfDisqusShortname}
</body>
</html>

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